Switch and signal system.



No. 807,103. PATENTED DEC. 12, 1 905. E. J. ADAMS.

SWITCH AND SIGNAL SYSTEM.

APPLICATION FILED MAR. s, 1905.

3 SHEETS-SHEET 1.

PATENTED DEC. 12, 1905.

E. J. ADAMS. SWITCH AND SIGNAL SYSTEM.

APPLICATION FILED MAB.6, 1905.

3 SHEETS-SHEET 2.

IATENTBD DEC. 12, 1905. E. J. ADAMS.

SWITCH AND SIGNAL SYSTEM.

APPLICATION FILED MABJS. 1905.

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wane/was fWM 4- @f mb UNITED- STATES PATENT oFFIoE.

EDWIN J. ADAMS, OF WACO, TEXAS.

SWITCH AND SIGNAL SYSTEM.

To aZZ whom it may concern:

zen of the United States, residing at Waco, in the county of McLennan, State of Texas, have invented certain new and useful Improvements in Switch and Signal Systems; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable Others skilled in the art to which it appertains to make and use the same.

This invention relates to railroads,and more particularly to track and signal operating mechanism therefor, and has for its object to provide a mechanism of this kind which may be operated by an engine and which will possess novel features,to be hereinafter described.

Another object is to provide a track-shift ing mechanism for use at intersecting tracks which will make it impossible for a train on one track to collide with a train on the other track.

Other objects and advantages will be apparent from the following description, and it will be understood that modifications of the specific construction shown may be made and any suitable materials may be used without departing from the spirit of the invention.

In the drawings forming a portion of this specification, and in which like characters of reference indicate similar parts in the several views, Figure 1 is a top plan view showing the present mechanism-employed in connection with intersecting tracks. Fig. 2 shows the present invention employed in the operation of signals. Fig. 3 is a top plan view showing the present invention employed as a switch-operating mechanism. Fig. tie a perspective view of one of the slides and the dog carried thereby. Fig. 5 is a vertical longitudinal section of the shifting mechanism. Fig. 6 is a perspective view of a semaphore, showing its connection with the shift-rod. Fig. 7 is a perspective view of the base of a switch-signal, a portion of the base being broken away to illustrate'the connection of the signal-upright with its shift-rod. Fig. Sisatop plan view of the sWitch-detent. Fig. 9 is a perspective view of the operating mechanism which is carried by the engine. Fig.

10 is a perspective view of the bottom of the shifting mechanism, one of the slides and its dog being shown in dotted lines. Fig. 11 is a top plan View of the crossing shift-rods at their point of intersection. Fig. 12 is a plan Specification of Letters Patent.

Application filed March 6, 1905. $eria1No. 24:8.642.

Patented Dec. 12, 1905.

view showing the application of the present Be it known that I, EDWIN J. ADAMS, a citiinvention to an electrically-operated system.

Referring now to the drawings, the present invention comprises the operatingmechanism 14:, which is carried by the engine and the operated mechanism, which is mounted upon the ground and which is connected with the tracks and signals.

The operative mechanism 14 consists of a plate 15, having transverse members 16 at its ends, and slidably engaged in these members and.extending therebeyond there is a centrally-disposed longitudinally-extending rod 17. At one end the plate 15 has an upwardlyextending hand-lever 18, pivotally connected therewith, and this lever is pivoted to the rod 17 for movement of the latter longitudinally when the hand-lever is moved. The members 16 extend laterally beyond the plate 15, and pivoted between these members 16 at opposite sides of the plate15 there are wings 19 and 20, which are movable to extend vertically or horizontally, and when in. their last-named position they extend beyond the members 16, the free edges of these wings being longitudinally convex, as shown at 20. Formed upon the upper surface of the plate 15 at opposite sides of the rod 17 thereare sleeves 21, which extend transversely ofthe plate, and slidably mounted in these sleeves there are blocks 22, which are slidable transversely of the plate15. At their outer ends the blocks 22 are bifurcated, as shown at 23, and pivoted in these bifurcations are the inner ends of arms 24, the outer ends of which are pivoted between the spaced ears 25, formed upon the inner surfaces of the wings19 and 20. Springs 26 are secured to the sleeves 21 and to the wings 19 and 20 and are arranged to hold the wings yieldably in their vertical positions, and when the wings are in such pojections come into engagement with the blocks, the latter are moved outwardly and the wings 19 and 20 are moved against the action of the LIO springs 26 to occupy their horizontal positions. The entire mechanism is secured to an engine, with the lever 18 lying within reach of the engineer and in such position that the wings 19 and 20, when they extend horizontally, project beyond the sides of the track over which the engine is traveling. The operative mechanism, whether it be used in connection with signals or with shiftable tracks, consists of-a shifting mechanism 28, which comprises a bottom plate 29, having a longitudinal slot therein and having end pieces 31 and 32. A top plate 33 is secured to the end pieces and lies parallel to the bottom plate and in spaced relation thereto, and this top plate is provided with a slot 34, which registers with the slot 30 for the reception of a sliding member 35, which is engaged at its upper and lower portions on the slots and extends vertically between the two plates. This sliding member includes laterally-extending portions 36, which are beveled at their forward outer corners, as shown at 37, and secured at one end to the sliding member and at its other end to the end piece 32 there is a spring 38, which holds the sliding member yieldably at the limit of its movement in the direction of the end piece 32. The sliding member 35 carries an upwardly-extendingspindle 39, which projects through the slot 34, and journaled upon this spindle above the top plate there is a roller 39. The member 35 carries forwardlyextending vertically-disposed spaced springloops 40, which occupy planes lying inwardly of the sides of the slots 30 and 34.

Formed at opposite sides of the slot 30, in the upper'face of the bottom plate 29, there are longitudinallyextending grooves 41, which extend to the forward end of the plate and which lie with their rearward ends forwardly of the loops 40 when the latter are in their normal positions as held by the spring 38. Formed in the upper face of the plate 29, at opposite sides of the grooves 41, there are semicircular grooves 42, these grooves being disposed one at each side of the slot 30 and outwardly of the grooves 41. At their rearward endsthe grooves 42 communicate with the grooves 41 at the rearward ends of the latter, the grooves 42 also communicating at their forward ends with the grooves 41 at points located between the ends of the latter. The under surface of the top plate 33 is grooved similarly to the upper surface of the bottom plate 29, the corresponding grooves of the two plates coinciding. Slides 43 are provided, which extend vertically and which have their edge portions slidably engaged in the coinciding grooves 41, and at their rearward ends these slides have dogs 44 pivoted. thereto for horizontal movement toward and away from the slots 30 and 34. These dogs 44 lie between the mutually adjacent faces of the top and bottom plate and have upwardly and downwardly extending pins 45, engaged therein at their rearward ends, these pins being disposed in recesses 46 and 47, formed in the upper and lower faces, respectively, of the dogs 44, and disposed between these pins and the ends of the recesses there are helical springs 48, which hold the pins yieldably projected,the latter being arranged for movement into the recesses against the action of the springs. These pins 45, lying in engagement with the coinciding grooves of the top and bottom plates, are movable from the grooves 41 to the grooves 42, and vice versa. At their forward ends the dogs 44 have inwardly-extending shoulders 49, which when the pins are in engagement with the grooves 41 extend beyond the adjacent edges of the slots 30 and 34 and terminate short of the opposite edges thereof.

When in position for operation, the mechanism just described lies with its rearward end, at which the end piece 32 is located, adjacent to a railroad-track, the top and bottom plates extending at right angles to the latter, and the roller 39 lies in position for engagement by the convex edge of one of the wings 19 and 20 of the operating mechanism 14. The bottom plate 29 has a forwardly-extending portion 50, to the outer end of which there is pivoted a transversely-extending lever 51, one

end of which is connected by means of a link 9 52 with one of the slides 43, while the other end is connected, by means of a link 53, with the other slide. Extending forwardly from the lever 51, at its pivot-point, there is an arm 54 for a purpose to be presently described.

When the roller 39 is engaged by one of the wings of the operating mechanism 14, the sliding member 35 is moved forwardly against the action of the spring 38. The slides 43 lie normally one at the forward limit of its movement and one at the rearward limit of its movement, and the pins of the dog carried by the last-named slide lie in position to enter the rearward end of the adjacent grooves 42. The bottoms of these grooves 42 slant upwardly and forwardly, so that the forward ends thereof lie slightly above the bottoms of the grooves 41, the resultant shoulders 55 receiving thereagainst the pins 45 of the forward dog.

When the member 35 is moved forwardly, as mentioned in the foregoing, one of its loops 40 engages the rearward dog 44, after which this dog, through further movement of the member 35, is engaged by the beveled portion 37 of one of the laterally-extending portions 36 and is moved by this portion to bring its pins 45 into the adjacent grooves 42. Further movement of the member 35 forwardly brings its other loop 40 into engagement with the forward dog 44, and this loop is sprung inwardly, it being susceptible of such movement until it passes the dog, when it springs back into position to engage the shoulder 49 of this dog. By this time the wing of the latter,

dog and slide moving the other slide and its dog forwardly through the medium of the links 52 and 53 and the lever 51, as will be readily understood, the pins carried by the dog of this forwardly-moving slide traversing the grooves 42, and thus holding the dog out of position for engagement by the adjacent loop 40 during the return movement of the It will be seen that after the operation just described the lever 51 lies with one -of its ends slanted toward and the other away from the end piece 31 and that the positions of these ends will bereversed by the next forward movement-of the member 35.

The pressure of the loop 40 against the shoulder 49 of the rearwardly-moving dog holds the pins 45 of this dog closely against the outer walls of the grooves 41, in which they lie, so that when the pins have come in a position to enter the rearward ends of the grooves 42, in which they are adapted for engagement, the pressure above referred to moves the dog pivotally and causes its pins to enter the grooves 42, this movement resulting in the disengagement of the loop 40 from the dog, and further rearward movement of the sliding member 35 under the action of the spring 38 is independent of the rearwardly-moved dog and slide 43. As mentioned above,-the beveled portions 37 ofthe laterally-extending portions 36 are arranged for engagement of the dogs 44 to move them out of the paths of movement of loops 40, and it will thus be seen that the dogs will be thus moved by these beveled portions should the operation of the dogs under the pressure of the loops 40 fail for any reason to take place.

In Fig. 1 of the drawings there are illustrated two intersecting tracks A and B, the latter being provided with two of the shifting mechanisms 28, disposed as described above and located at opposite sides of the track A. The arms 54, carried by the levers 51 of the two mechanisms,'are connected by means of a rod C, and this rod is connected, by means of a bell-crank lever D, with a shift-rod E, which extends parallel to and at one side of .the track A. At opposite sides of the track B the track A is provided with rail-sections F, having end portions F, which are movable into and out of alinement with the adjacent portions of the rails. These movable portions F are connected with the shift-rod E in such a way that when the shift-rod is moved longitudinally in one direction the movable portions F are moved simultaneously out of alinement with the adjacent portions of the rails, movement of the shift-rod in the 1 ,other direction returning the movable portions F to their original positions. Semaphores G are provided for the track A and are connected with the shift-rod E in such a way that when this shift-rod is moved to bring the portions F out of alinement with the adjacent portions of the rails the semaphores are moved into operative position, these semaphores being returned to inoperative position when the rails .assume their normal positions. It will thus be seen that if a train is approaching the track A over the track B and has one of the wings of its mechanism 14 projected for engagement of the rollers 39 of the shifting mechanisms the engagement of the roller with the first shifting mechanism, which will occur before the train reaches the crossing, will move the semaphores G into position to indicate to the engineer of a train on the track A that a train is approaching over the track 13, and at the same time the track A will be broken, as described above,

so that if the engineer should disregard the.

signals his train will be derailed, thus preventing a collision at the crossing. After the train has crossed the track A the wing of its mechanism 14 will come into engagement with the other shift mechanism to move the signals of the track B into inoperative position and to return this track to its original condition.

It will be understood that the track A is also provided with the two shifting mechanisms, and in the drawings the shift-rod for the track B is indicated at H. This shift-rod extends beneath the shift-rod E, and the two shift-rods are provided with projections E and H, respectively, upon their mutually adjacent faces. The arrangement of these projections is such that when the shift-rod E is in position to hold the semaphores (:r in operative position the projection E lies in the path of movement of the projection H to prevent movement of the shift-rod H, thus preventing a train on the track A from setting the signals and breaking the rails of the track B. On the other hand, when the shift-rod H is moved to set the signals for the track B its projection H comes into the path of movement of the projection E to prevent the setting of the signals for the track A. 7

At their ends the projections E and H are provided with rollers I, the roller of each shift-rod being disposed to receive the edge portion of the other shift-rod and its projection thereagainst to reduce friction, and each shift-rod rests at its side opposite to that which is engaged by the roller of the other shift-rod against supporting rollers K, as shown in Fig. 11.

In Fig. 3 the present invention is shown applied to a switch, and the arms 54 are connected by means of rods 56 with a bell-crank lever 57, this bell-crank lever being connected, by means of a shift-rod 58, with the movable switch-rails 59. This shift-rod passes through the cylindrical base of a switch-signal 61, this base being hollow and having a verticallyextending signal-standard 62 rotatably mounted therein. Within the base the standard has a laterally-extending arm 63, which is engaged between spaced pins 64, carried by the shiftrod, so that when the shift-rod is moved to move the switch the signal-standard will be revolved to change the position of the signal 65, carried by the upper end of the standard and which indicates the position of the switch. Above the base the standard 62 is rectangular in cross-section. Slidably disposed upon the upper face of the base there is a member 67, having a central vertical opening 68, which receives the angular portion of the standard revolubly therewithin, and extending longitudinally of the member 67 and communicating at one end with the opening 68 there is a slot 69, which is arranged to snugly receive the angular portion of the standard therewithin, so that the member 67 may be first slid to bring its slot 69 into engagement with the angular portion of the standard and may then be used as a handle to revolve the standard, it being understood that this member is used only when it is desired to set the switch and signal by hand. The member 67 has a downwardly-turned portion 70 at its end opposite to the slot 69, and when the member is in position to lie with the standard 62 extending through its opening 68 this portion 70 lies within a recess 71 in the side of the base 60, this recess opening through the top of the base, as shown. The engagement of the portion 70 in the recess 71 prevents rotation of the member 67, and in order to prevent movement of the member 67 to bring its portion 70 out of the recess, a staple 72 is provided, which extends into the recess 71 from the back of the latter and lies in a passage 73, formed through the portion 70, the bight of the staple projecting beyond the outer face of the portion 70 for thereoeption of a lock 74 to prevent diseugagementof the downwardly-turned portion 70 from the staple.

A detent 75 is provided and as shown in Figs. 3 and 8. In the former it is illustrated as being employed in connection with the switch-operating mechanism; but itwill be understood that it may be incorporated in any of the systems illustrated. The object of this detent is to prevent malicious shifting of the switches or signals. In Fig. 8 there is shown a shift-rod 76, which may be any one of the shift-rods previously described and which con sists of two sections 77 and 78. The section 77 carries an upwardly extending pin 79, which is slidably engaged in a longitudinal slot 80, formed in the section 78, the two sections overlapping, as shown. At opposite sides of the pin 79 the section 77 is provided with cylindrical recesses 81 and 82, respectively, which open through the side edge of Located at this side of the shiftthe section.

rod there is a casing 83, has its end adjacent to the shift rod open, and slidably mounted in this casing there is a block 84,'

which is held normally projected beyond the open end of the casing by means of a helical spring 85, arranged for this purpose, the block being movable into the casing against the action of the spring. The outwardly-project ing portion of the block is rounded, as shown at 86, and this rounded portion carries at its center an outwardlyprojecting pin 87, arranged for interchangeable engagement in the recesses 81 and 82 and which lies normally in engagement with one of these recesses, the rounded surface 86 of the block resting against the section 77 of the shift-rod. The section 78 of the shift-rod has a laterally-extending enlargement 88, which extends beyond therecessed side of the section 77 and which lies parallel with the slot 80. This enlargement 88 is thus so disposed that the outwardly-projecting portion of the block 84 lies in the path of movement of the enlargement. It will thus be apparent that when the shift-rod 76 is moved the section 78, which is connected at its end opposite to its slot with the mechanism 28 described above, is moved initially independently of the section 77, which brings the projection 88 into engagement with the block 84, thus moving this block to bring its pin 87 out of engagement with the recess in which the pin lies, and when the pin 79 comes into engagement with the opposite end of the slot the movement of the section 78 will be communicated to the section 77 to operate the track or signals, as the case may be. When this has been done, the other recess of the section 77 will lie in position to receive the pin 87, and the projection 88 having passed beyond the block 84 this block will be moved by the spring to engage the pin 87 in the other recess, thus preventing return movement of the section 77.

In Fig. 2 there is shown a track 89, having a curve therein, and at opposite ends of the curve there are located two of the mechanisms 28. In this instance the levers 51 of the mechanisms are provided with arms 51', which extend oppositely to the arms 54, and the arms 51 of the two mechanisms are connected by a cable M. The arms 54 of the mechanisms are connected by a cable 90, and these cables M and 90 are connected with the ends of centrally-pivoted levers 91, having laterally-extending arms 91, which are connected with semaphores 92 for operation of the latter, as will be readily understood. It will thus be apparent that operation of one of the mechanisms 28 will move the semaphores into one position and operation of the other mechanism 28 will move the semaphores into their other positions.

In Fig. 12 the present invention is shown applied to an electrically-operated system, the arms 54 being connected by means of a rod 93, which carries contact-pieces 94 and 94E movable with the rod into and out of entheir weights and blades.

gagement with contact-pieces 95 and 95, respectively, these contactpieces having the wires 96 of an electric circuit connected therewith.

The semaphores mentioned above consist of uprights 97 to the upper ends of which are pivoted signal-arms98, the latter including blade ends 99 and weighted ends 100, the arms being pivoted to the uprights between Rods 101 are connected at their upperends to the blades 99 and at their lower ends to rock-shafts 102, journaled transversely of the uprights adjacent to the bottoms thereof. Each of these rockshafts has cranks 103 and 104 at its ends, with one of which the rod 101 of the semaphoreis connected. In Fig. 6 one of these semaphores is illustrated, and the rod 101 is illustrated as secured to the crank 103, the crank 104: having one end of a link 105 pivoted thereto. The opposite end of this link is pivoted between ears 106, carried by the shift-rod operating the semaphore, which is indicated at L for operation of the semaphore when the rod is moved. The arrangement is such that when the shift-rod is moved to move the link the shaft 102 is rocked to draw the rod 101. downwardly, thus moving the blade 99 of the signal-arm downwardly and raising the weighted end of the arm. When the shift-rod returns to its other position, the parts are moved into their other positions (shown in Fig. 6) aided by the weighted end 100 of the signal-arm.

Mounted upon the forwardly-extending portion 50 of each of the mechanisms'28 there is a signal N, which is connected with the adjacent lever 51 for operation when.the lever is moved pivotally, and these signals are arranged to indicate to the engineer of a train the condition of the switch which he is approaching. Another signal 0 is connected with the system for operation when either of the mechanisms 28 is operated, and this signal O is arranged to indicate to the. engineer of a train whether or not the system has opera'ted correctly.

What is claimed is-- 1. In a system of the class described, the

combination with operative mechanism, of a shift-rod connected with said mechanism for operation thereof, means for moving the shiftrod, said means comprising a slidable member, loops carried by the slidable member,

slides, dogs carried by the slides and arranged for alternate engagement by the loops of the slidable member for movement of the slides with said member, connections between the slides and the shift-rod for movement of the .latter when the slides are moved.

bottom plates provided with registering longitudinal slots, a member slidably engaged in the slots and extending between the plates, means for holding the member slidably at one limit of its movement, loops carried by the member, slides engaged in the plates for movement longitudinally thereof, dogs carried by the slides and movable into and out of position for engagement by the loops for movement of the slides with the member, means for moving the dogs of the slides out of position for engagement by the loops,- said means being arranged to thus move one of the dogs when the member is moved to engage one of its loops with the other dog, a rock-lever, links connected with the slides and with the rock-lever for movement of the latter when the slides are moved, connections between the rock-lever and the operative mechanism for operation of the latter when the rock-lever is moved, and means carried by the movable member by which it may be moved.

3. The combination with a switch and signals, of operating means comprising spaced parallel slides, dogs pivoted to the slides and movable into and out of position to extend into the space between the latter, a sliding member, loops carried by said member and movable with the member into and out of the space between the slides, a rock-lever, links connected with the slides and with the rocklever and arranged to hold one of the slides at one limit of its movement when the other slide is at the opposite limit of its movement, said dogs being adapted for engagement by the loops for movement of the slides with the slidable member, means for moving the dog of one member out of position for engagement by one of the loops when the member is moved to engage its other loop with the other dog, means for holding the sliding member yieldably at the limit of its movement away from the slides, and means connected with the rock-lever and with the switch and signals for operation thereof when the rockleveris moved.

4. The combination with intersecting tracks having movable rails, of a shift-rod for each track, connections between the shift-rods and movable rails formovement of the rails when the shift-rods are moved longitudinally, said shift-rods being disposed one above the other and at right angles to each other, and projections carried by the shift-rods, the projection of one shift-rod being arranged for movement tolie in the path of movement of the projection of the other shift-rod when the first-named shift-rod is at one limit of its movement to prevent movement of the second-named shift-rod, the projection of the second-named shift-rod being arranged to lie in the path of movement of the projection of the first-named shift-rod when the secondnamed shift-rod is at one limit of its movement to hold the first-named shift-rod against movement.

5. An operating mechanism for signal and switch systems comprising spaced top and bottom plates, a member slidably disposed between the plates, a springsecured to the member and arranged to hold the latter yieldably at the rearward limit of its movement, forwardly-extending loops carried by the member,'slides disposed between the plates at opposite sides of the paths of movement of the loops, said slides being arranged for forward and rearward movement, dogs carried by the slides and movable into and out of position to extend into the paths of movement of the loops, said slides being arranged to lie at the opposite limits of their movement from each other, means carried by the movable member for moving the rearmost dog out of position for engagement by one of the loops when the member is moved into position to engage its other loop with the other dog, the dog thus engaged and its slide being arranged for movement rearwardly with the movable member, a rock-lever connected at its ends with the slides for movement when the slides are moved, said lever being arranged for connection with an operative mechanism for operation of the latter when the lever is moved, and a projection carried by the movable member and adapted for engagement by an instrument carried by a piece of rolling-stock to move the member against the action of the spring and into position for engagement of its loops with the dogs.

6. The combination with intersecting tracks each provided with movable rails, of a shiftrod for each track, connections between the shift-rods and the movable rails for movement of the rails when the shift-rods are moved, said shift-rods being disposed in crossrelation and projections carried by the shiftrods, the projections of the shift-rods being arranged for movement with their rods into and out of the paths of movement of each other.

7. The combination with 'a shift-rod, of a revolubly-vertical standard, a base in which the standard is journaled, connections between the standard and the shift-rod for rotation of the former when the latter is moved longitudinally, a horizontal member having a central opening therein in which the standard is revolubly engaged, said member having a slot communicating with its opening, and

adapted for engagement by the standard for' movement of the standard with the member, said member'being movable to engage the standard in its slot, and means for holding the member against such movement.

8. An operating instrument for rollingstock comprising pivoted wings movable into nd out of position to extend laterally, means for holding the wings yieldably out of such position, and means for moving the wings against the action of the holding means, said wings when in their laterally-extending position being adapted for engagement of trackoperating mechanism to actuate the latter.

9. In a system of the class described, the combination with operative mechanism of operating means therefor comprising a slidable member, loops carried by the 'slidable member, slides, dogs carried by the slides and arranged for engagement by the loops for movement of the dogs and slides with the member and connections between the operating means and the operative mechanism for operation of said mechanism when slides are moved.

10. In a system of the class described the combination with crossed shift-rods arranged for longitudinal movement and having projections thereon the projection of each shiftrod being arranged to lie at times in the path of movement of the projection of the other shift-rod to hold the latter against movement means for reducing the friction between the mutually-engaging portions of the shift-rods and projections and braces for each shift-rod said braces being located at the opposite sides of their shift-rods from the projection of the other shift-rod.

11. The combination with intersecting tracks each provided with rails movable into and out of operative position, of a shift-rod for each track, connections between the shift-rods and the movable rails to their respective tracks for movement of said rails when the shiftrods are moved, means operable by rollingstock for moving the shift-rods, and signals connected with the shift-rods for operation thereby said signals being arranged to indicate the position of the movable rails.

12. An operating mechanism for signal and switch systems comprising spaced plates, a member slidably disposed between the plates for movement longitudinally thereof, forwardly-extending spring-loops carried by the member, said plates having coinciding grooves therein located at opposite sides of the paths of movement of the loops, slides engaged in the coinciding grooves and arranged for movement longitudinally of the plates said plates also having coinciding arcuate grooves therein adjacent to the rearward ends of the firstnamed grooves and communicating at their ends therewith, the convexities of said arcuate grooves being directed outwardly, dogs pivoted to the slides, pins carried by the dogs and extending into the grooves, said dogs having shoulders arranged to project into the paths of movement of the loops for engagement thereby to move the dogs and slides rearwardly with the loops, connections between the slides arranged to hold the slides at opposite limits of their movements and means for moving the dogs to bring their for connection W1th aswitcli or slgnal system pins into the arcuate grooves and to bring for operation thereof. m their shoulders out of position for engagement In testimony whereof I afiix my signature 1n by the loopswhen said dogs are at the rearpresence of two witnesses.

ward limits of their movements, said dogsly- EDWIN ADAMS' ing in position for engagement by the loops when the dogs are at the forward limits of 1 their movements said slides being arranged I Witnesses:

FRANK (J. HALL, HY. E. CHANDLEE. 

